Re: [PATCH v2 2/3] DAX-DIO: skip DAX to non-DAX if unsupported

[Xiong Zhou <xzhou@redhat.com>]

On Tue, Apr 11, 2017 at 07:44:10PM +0800, Eryu Guan wrote:
> On Mon, Apr 10, 2017 at 02:05:52PM +0800, Xiong Zhou wrote:
> > By tweaking SCRATCH_DEV by ndctl, only run DAX mapped
> > area DIO to non-DAX area tests when pmem device is in
> > "memory mode".  > > 
> > Signed-off-by: Xiong Zhou <xzhou@redhat.com>
> > ---
> > 
> > v2:
> >   umount/check scratch fs after test
> >   restore SCRATCH_DEV mode in cleanup
> >   fix variable names
> > 
> >  tests/generic/413 | 26 +++++++++++++++++++++++++-
> >  tests/xfs/260     | 31 ++++++++++++++++++++++++++++++-
> >  2 files changed, 55 insertions(+), 2 deletions(-)
> > 
> > diff --git a/tests/generic/413 b/tests/generic/413
> > index a1cc514..fbe8f11 100755
> > --- a/tests/generic/413
> > +++ b/tests/generic/413
> > @@ -34,6 +34,9 @@ _cleanup()
> >  {
> >  	cd /
> >  	rm -f $tmp.*
> > +	# restore SCRATCH_DEV to original mode
> > +	$NDCTL_PROG create-namespace -f -e $scratch_dev_namespace \
> > +	  -m $scratch_dev_mode > /dev/null 2>&1
> >  }
> >  
> >  # get standard environment, filters and checks
> > @@ -47,9 +50,13 @@ _supported_fs generic
> >  _supported_os Linux
> >  _require_test
> >  _require_scratch_dax
> > +# fsck manually after tests as we will reconfig SCRATCH_DEV
> > +_require_scratch_nocheck
> >  _require_test_program "feature"
> >  _require_test_program "t_mmap_dio"
> >  _require_xfs_io_command "falloc"
> > +_require_ndctl
> > +_require_jq
> >  
> >  prep_files()
> >  {
> > @@ -110,7 +117,7 @@ t_both_nondax()
> >  t_mmap_dio_dax()
> >  {
> >  	t_both_dax $1
> > -	t_dax_to_nondax $1
> > +	[ $skip_dax_to_nondax -eq 0 ] && t_dax_to_nondax $1
> >  	t_nondax_to_dax $1
> >  	t_both_nondax $1
> >  }
> > @@ -126,6 +133,21 @@ do_tests()
> >  	t_mmap_dio_dax $((64 * 1024 * 1024))
> >  }
> >  
> > +skip_dax_to_nondax=0
> > +# config SCRATCH_DEV to memory mode to support DAX mapped
> > +# area DIO to non-DAX area.
> > +
> > +# save original mode
> > +scratch_dev_mode=$(_ndctl_get_pmem_key_value $SCRATCH_DEV mode)
> > +
> > +# get its namespace
> > +scratch_dev_namespace=$(_ndctl_get_pmem_key_value $SCRATCH_DEV dev)
> > +
> > +# skip dax to non-dax dio if config fails
> > +$NDCTL_PROG create-namespace -f -e $scratch_dev_namespace \
> > +  -m memory > /dev/null 2>&1 \
> > +  || skip_dax_to_nondax=1
> > +
> 
> I'm not sure if it's proper to change the pmem device mode in tests.
> IMO, fstests just takes use of user specified TEST|SCRATCH_DEV and
> checks if they meet our requirements.
> 
> So I think the correct way is just check the mode of pmem device and
> _notrun if the mode isn't compatible with this test.

I'm working on splitting this case into 2 cases. Running dax_to_nondax
solely, _notrun if not compatible. Since only this sub case really need
pmem device in specific mode.

Thanks,
Xiong

> 
> Thanks,
> Eryu